Combination pivoting and sliding block firearm action



J. .LE B; ARBUCKLE Feb. 10, 1953 COMBINATION i qvo'rmc AND SLIDING BLOCK FIREARM ACTION 4 Sheets-Sheet 1 Filed Nov. 22, 1950 F1 E-J-E'INVENTOR JZkn 276B. flrbuckle ATTORNEY Feb. 10, 1953 LE 5, ARBUCKLE 2,627,687

COMBINATION PIVOTING AND SLIDING BLOCK FIREARM ACTION Filed Nov. 22, 1950 4 Sheets-Sheet 3 INVENTOR Jhn Z65. flrbuckle ATTORNEY a2 '7 y o 3 J. LE B. ARB UCKLE 2,627,687

I COMBINATION'PIVOTING AND SLIDING BLOCK FIREARM ACTION Filed Nov. 22, 1950 4.Sheets-Sheet 4 FIGEI INVENTOR John Z65 flrb uck'le' ATTORNEY Patented Feb. 10, 1953 UNITED STATES TENT OFFICE COIVIBINATION PIVOTING AND SLIDING BLOCK FIREARM ACTION John Le B. Arbuckle, Sunbury, one-half to Hugh E. Grashel,

Ohio, assignor of Gahanna, Ohio 4 Claims.

The present invention relates to firearms, and has particular reference to an improved firing action to be used in connection with precisiontype single shot target rifles.

This invention has for its primary objective the provision of an improved firearm action which is particularly adapted for use in connection with precision built target rifles, and which is characterized by structurally rugged and durable elements which function one with the other to provide a precision-type firing mechanism devoid of undesired play and which greatly reduces the amount of wear between relatively movable parts of the mechanism in comparison with previously known types of firearm action-s.

Another object of this invention is to provide an action for firearms wherein the separate elements or parts of the action are readily accessible for purposes of disassembly, cleaning, repair, or replacement.

It is a further object of the present invention to provide a firearm action which comprises a stationary frame which is formed at one end to receive the chambered end portion of a barrel and at its opposite end to receive the shank of a stock, and which detachably mounts a combination of moving elements which may be quickly and easily detached from the frame and the firearm as a unit through the simple removal of a single pivot pin to provide access to the working mechanisms of the firearm to facilitate cleaning, adjustment, or replacement of the elements of the actual firing mechanism without necessitating the complete disassembly of the firearm.

Yet another object of this invention is to provide a firearm action which embodies a trigger and an associated trigger spring mechanism which is adjustable to vary the amount of manually applied force required to move the trigger between its cocked and firing positions.

These and various additional objects and advantages will become more readily apparent with a further understanding of the present invention which may be had by reference to the following description and the accompanying drawings, wherein:

Fig. 1 is a top plan view of a firearm action formed in accordance with the present invention;

Fig. 2 a side elevational view thereof;

Fig. 3 is a medial longitudinal vertical sectional view taken through the firing mechanism and showing the various parts thereof in their cartridge-firing positions;

Fig. 4 is a similar view showing the action in an intermediate cocking position;

Fig. 5 is a similar vow of the action with the various parts thereof occupying their cartridgeextracting and receiving positions;

Fig. 6 is a similar view of the action in its fully cooked position with the associated safety in a safe positon;

Figs. 7-9 are detailed transverse vertical sectional views taken along the lines 8-8, and 9-9, respectively, of Fig. 3;

Fig. 10 is a detailed horizontal view along the line 10-49 of Fig. 3; and

Figs. 11-13 are detailed perspective views of the pivoting block, sliding block, and cocking lever, respectively, of the present action.

Fig. 14 is a medial longitudinal vertical sectional view of the extractor engaging a cartridge.

Fig. 15 is a transverse vertical sectional view of the extractor engaging a cartridge.

Referring to the drawings, the numeral 20 designates generally the stationary frame portion of the present firearm action. At its forward end, the frame 20 is formed with a cylindrical boss formation 22 in which is formed a threaded barrel-receiving opening 23 for the threaded reception of the chambered end of a rifie barrel 24. At its rearward end, the fame 20 is formed with a substantially rectangular and inwardly tapered stock-receiving opening or recess 25 which receives the shank portion 28 of a shoulder stock 21. Intermediate its ends, the frame 20 is formed with transversely spaced vertically extending side walls 28 defining an open-ended vertically arranged chamber between the barrel-receiving boss 22 and stock-receiving region 25. Advantageously, the stock-receiving region 25 of the frame 28 is provided with an outwardly projecting and internally screwthreaded attachment tube 30 which is arranged to extend within a cooperative opening formed in the shank of the stock 2'! and to receive a cooperatively screw-threaded shaft or rod 32 which extends through the stock 21 and into the screwthreaded chamber of the tube 30 to securely fasten the stock 21 to the rear end of the frame 26. In this manner, the stock 2'! may be easily detached from the remaining portion of the firearm simply by disconnecting the single rod 32 from the screw-threaded extension 30 of the frame.

Extending transversely between the spaced side walls 28 of the frame, below the barrel-receiving opening 23, is a smooth-surfaced pivot pin 34. Preferably, the pin 34 is provided at one end with an enlarged head 35 which is slotted to receive the driving head of a screwdriver, and which is provided on its periphery with an arcuate recess 35 arranged to be brought into alignment with a segment of the circular head portion of a lock screw 31 to permit removal of the pin 34 from the frame. The lock screw 31 functions to prevent accidental removal of the pin 34 when the latter is rotated t move the slot 35 out of registration with the head of the lock screw, and it will be understood that this assembly is common to many types of firearms, and as such, constitutes no particular part of the present invention. Ad-

vantageously, the depending side walls 28, in the region of the pin 34, are provided on their inner sides with spaced wear plates or blocks 38 which are rigidly joined with the side walls 28, but

which may be removed for replacement if so desired. Extending between the Wear blocks 38 of the frame are a pair of transversely spaced ears 40 formed integrally with a pivoting block 42. The spaced ears 40 are provided with transversely aligned openings 44 through which the pivot pin 34 extends to support the pivoting block 42 for pivotal swinging movement. The block 42, in addition to the spaced ears, is formed to provide a perpendicularly related breechblock portion 45 which, when the block occupies its battery position, lies in abutting engagement with the walls of the cylindrical boss formation 22 of the frame which define the barrel-receiving opening 23. The flat forward face of the breechblock portion of block 42, in operation, abuts the cap end of a cartridge when the latter is positioned Within the chamber of the barrel 24. The rear side surface of the block 42 is formed in its intermediate region with an arcuate recess 48, and is provided at its lower end with a rearwardly projecting and arcuately rounded cam surface 50.

Pivotally carried upon the pin 34 between the transversely spaced ears 40 of the block 42 is a manually operated cocking lever 52. As shown in detail in Fig. 13, the cocking lever 52 is provided with an intermediate tubular formation 54 through which is formed a transversely extended bore 55 for the reception of the pivot pin 34. Additionally, the cooking lever is provided with a depending handle arm'58 by which the cooking lever may be swung or rocked about the pivot pin 34. Normally, the handle 38 extends rear- Wardly from the bottom of the frame 20, and whenoccupying a cooked position, is disposed in substantially parallel relation to the shank portion of theistock 21. The cocking lever 52 is further provided with an outwardly projecting lip 60 which, as shown particularly in Fig. 4 of the drawings, is arranged to engage a shoulder 62 formed on the pivoting block 42 between the cars 40 to swing the pivoting block in a clockwise direction about the pivot pin 34 and out of its battery position in abutment with the chambered end of the barrel. The cocking lever 52 is further provided with a second outwardly extending block-like arm 64 of relatively greater width than the intermediate region 54 of the cooking lever, and which extends rearwardly of the vertical chamber of the frame and terminates at its outer end in a pair of transversely spaced ears 65 which rotatably support a pair of rectangular guide blocks 66 projecting laterally outwardly from either side of the block 54.

The guide blocks 66 carried on the cooking lever 52 are slidably received in a pair of spaced parallel guide tracks 58 formed on the inner side surfaces of a sliding block 70. The sliding block is provided with transversely spaced side walls 12 4 at its forward end, and terminates at its rearward end in a chambered yoke region 14. The yoke region 74 of the sliding block is rounded on its upper rear side, as at it, in order that the block may clear the rear side wall 18 of the vertically arranged frame chamber. In addition to the spaced horizontally disposed guide track 58, the sliding block is provided with spaced parallel and vertically arranged guide tracks which slidably receive vertically arranged and laterally projecting guide formations 82 formed on either side of the pivoting block 42. Thus the pivoting block 42 fits within the vertical chamber defined by the side walls 72 of the sliding block. Rearwardly of the spaced side walls #2, the sliding block, in its yoke region 74, is recessed to provide a dome-shaped hammer-receiving chamber 84. Extending between the spaced side walls 12 of the sliding block are a pair of cylindrical spacer projections 85 formed on either side of a vertically arranged hammer 88. The transversely extending spacer projections 85 are provided with a bore for the reception of a smooth-surfaced hammer-supporting pin 99 which extends between the spaced side walls 72 of the sliding block. The pin is provided at one end with an enlarged tapered head 32 which fits within a tapered socket 54 formed in one of the side walls (2 of the sliding block, while the opposite end of the pin 95 extends Within an opening 98 formed in the opposite side wall 72 of the sliding block. Advantageously, the side wall 12, which is provided with the head-receiving socket 94, may alsobe formed with an adjacent lock screw opening 93 for the reception of a lock screw, not shown, of the type indicated at 3?, which functions to hold the headed region of the hammer 94 in a flush position with respect to the outer surface of the sliding block and against withdrawal from the side wall 12 of the sliding block. The hammer pin 35 functions to pivotally support the hammer 88 and its associated cylindrical spacer projections 85. Wound about one of the projections 85 is a torsion spring 493 which has one of its ends held within an opening, as at 152, formed in the hammer 88, and its opposite end positioned within an opening formed in the adjacent side wall 12 of the sliding block 15. The hammer 38 is formed on its upper forward side with a flat striking face I34 which is arranged to swing into striking engagement with the rearward end of a firing pin m5 which extends longitudinally through a suitably chambered opening formed in the upper head portion of the pivoting block 42. The firing pin I 66 is formed at its rearward end with a relatively enlarged cylindrical portion 948 and terminates at its forward end in a relatively reduced cylindrical portion H5 arranged to project outwardly from the fiat breechblock portion 45 of the pivoting block for firing engagement with the cap of a cartridge positioned Within the chamber of the barrel 24. The relatively enlarged cylindrical portion Hi8 of the firing pin is provided on one side with an elongated slot H2 into which extends the inner end of a retaining screw 4 l 4 extending through one side of the head portion of the pivoting block 42. The retaining screw H4 holds the firing pin 5% within the chamber of the pivoting block 42 to permit limited longitudinal sliding movement of the firing pin within the pivoting block, and further provides for removal of the firing pin in its entirety from the pivoting block when access thereto is desired. Normally, with the striking face I 34 of the hammer 88 in engagement with the rear end'of the firing pin I85, the forward pointed extremity of the firing pin projects outwardly beyond the breechblock portion of the pivoting block, as shown in Fig. 11, but as the striking face I54 of the hammer 88 is moved out of engagement with the rear end of the firing pin, the same moves rearwardly of the pivoting block and projects slightly beyond the rearward flat face thereof.

The hammer 88 is further formed to provide a cooking abutment II4 which projects in right angular relation to the firing face I04 for engagement with the cam projection 50 formed on the pivoting block 42. Relative downward movement of the sliding block with respect to the pivoting block 42 functions to engage the cocking projection II4 on the hammer with the cam face 50 of the pivoting block to swing the hammer about its pivot pin 98 against the action of the torsion spring I55. Further, the hammer 88 is formed on its lower side with a sear-receiving shoulder III; which is engageable with an outwardly projecting sear H8 formed on a trigger I28 to releasably hold the hammer 88 in its cocked position. The trigger I25 is formed with a centrally disposed opening through which extends a pivot pin I22 carried between the side walls I2 of the sliding block I5. As with the hammer pin 95, the trigger-supporting pin I22 is received within transversely aligned openings formed in the respective side walls of the sliding block,.with one end of the pin I22 being headed and received within a tapered socket I24 formed in the lower side of one of the side walls I2. The trigger I is formed to provide a downwardly projecting arcuate finger-receiving lever I26 which is formed on its rear side with an enlarged vertically arranged chambered boss I28 through which extends a cylindrical bore I38. The cylindrical bore I35 of the trigger screw-threadedly receives at its lower end a threaded plug I32, the inner end of which abuts one end of a coiled compression spring I34 whose opposite end engages a plunger I35 which projects outwardly from the opposite end of the tub lar boss I28 for engagement with a cross piece I33 formed on the sliding block l5 between the side walls l2. It will be noted that the upper end of the tubular extension I28 of the trigger is normally spaced from the lower surface of the cross piece I38 to permit limited pivotal movement of the trigger in response to manually applied forces. By increasing or decreasing the tension upon the compression spring I34, by adjustment of the screw I32, the forces necessary to rock the trigger I about the pin I22 may be correspondingly increased or decreased to determine the trigger pull of the action.

As shown particularly in Fig. 6 of the drawings, the hammer 88 is provided upon its upper surface with a shouldered detent I48 which is arranged to receive a safety plunger I42 extending through the stock-adjoining region 25 of the frame 20. The safety plunger I42 is slidably carried within a cylindrical chamber formed in the stock-engaging region of the frame, and is formed at its rear end with rack teeth I44 carried in meshing engagement with the teeth I45 formed on a segment of the lower surface of a tubular casing I48. The casing I48 is rotatably mounted on a pin 15!! which extends through the casing I48 and an adjoining stationary bearing sleeve I52 carried on the upper surface of the stock-adjoining portion of the frame. The shaft I55 is headed at one end, as at I56, and provided at its opposite end with a screw-threaded region, not shown, which is threaded with a headed nut I58 carried at-the opposite end of the casing I48. The casing I48, on its outer surface, is provided with an actuating lever I58 by which the casing I48 may be rotated to move the safety plunger I42 into and out of engagement with the detent I40 on the hammer 88. Advantageously, the leading end of the safety plunger I42 is beveled and arranged to wedge against the shouldered surface of the detent l4ii on the hammer in a manner to swing the hammer 88 slightly in a clockwise direction as viewed from Fig. 6 and to move the searreceiving shoulder I I6 slightly out of engagement with the sear I I8 of the trigger. Thus, when the safety is applied, the tension of the hammer spring is removed from the sear H8 and is taken up by the safety plunger I42 to permit the trigger I28 to be freely moved without releasing the hammer.

As shown particularly in Fig. '7 of the drawings, the frame 25 is channeled along its inner side walls to receive an extractor I52 within guide slots I54 disposed below the barrel-receiving boss 22, The extractor I62 comprises a vertically arranged arm which is arcuately recessed at its uper end, as at I68, and which is chambered to receive a spring-pressed cartridge-engaging lip IIE! which projects upwardly from the extractor for engagement with the extractor groove I72 formed on a rimless-type cartridge II4. Additionally, the extractor I52 is formed with laterally extended guide ceived within the guides I64 of the frame to permit straight longitudinal sliding movement of the extractor. The separate legs I15 are slotted a distance inwardly from their outer ends and join with one another in a cross web I18 which is arranged to be engaged by the projection 68 formed on the cooking lever 52 substantially immediately following the engagement of the proiection 65 with the shoulder 52 of the pivoting block 42. Thus, the extractor I62 is moved rearwardly out of engagement with the barrel-receiving boss 22 of the frame by the swinging movement of the cooking lever 52, immediately following engagement of the pivoting block 42 by the projection 55 of the cooking lever.

Referring particularly to Figs. '7 and 10 of the drawings, it will be noted that the central portion 54 of the cooking lever 52 is reduced on one side to provide a cylindrical sleeve I84 around which is wound a torsion spring I85. Adjacent to the sleeve !84 of the cooking lever is a cylindrical spanner nut I88 which is rotatably carried within an opening formed in one of the ears 48 of the pivoting block 42. The nut I88 receives the opposite end of the torsion spring I85, and is provided upon its outer side wall with a plurality of wrench-receiving openings I98 by which the nut I88 may be located to adjust the tension of the torsion spring I88. A locking screw I92 is provided between the nut I88 and the ear 4!] of the pivoting block 42 to hold the nut I88 in its desired adjusted position. The opposite end ofthe torsion spring 585 fits within an opening formed in the central portion 54 of the cooking lever and functions to urge the cocking lever 52 to its closed position, as shown in Figs. 2 and 3 of the drawings, in substantial parallelism with respect to the shank 25 of the stock. Thus, movement of the cocking lever 52 is biased between the positions shown in Figs. 3 and 4, wherein the sliding block 55 is initially moved downwardly with respect to the pivoting block 42. In this manner, the cocking lever 52 and the sliding blocks.

legs which are slidably re 10 are prevented from loosely falling downwardly T out of their battery positions, and by reason of the adjustable nature .of the nut I 88, the tension of :the torsion spring I186 maybe adjusted to assure the return of the cocking lever to its battery position and the prevention of such lever from sliding downwardly by gravity.

In operation, assuming the chamber of the barrel'to be empty, and the hammerilt to occupy its fired'position as shown in Fig. 3, the action is cooked by swinging the handle 58 of the cooking lever in a clockwise direction to slide the sliding block 10 downwardly behind the pivoting block 42,-thus moving the hammer 88 to its cocked position as the projection N4 of the hammer slides over the cam face 59 of the pivoting block. Thereupon, the pivot-ing blockis engaged by the lip:60 of the cocking lever and'swings backwardly in a clockwise direction to gain access to the chamber of the barrel 2Q, whereupon the cartridge 14 is inserted within the chamber of the barrel and the cocking lever 52 returned to its battery position as shown in Fig. 6. In this position, :the sear-engaging lip I N5 of the hammer is normally held by the sear H8 of the trigger. If desired, the safety plunger M2 may be brought into engagement with the detent I40 of the hammer by rocking the lever Iii!) backwardly. With thesafety applied, as shown in Fig. 6, the tension of the hammer spring 108 is removed from the sear H8 due to the slight movement of the hammer '88 in a clockwise direction as viewed from Fig. ,6, by reason of the beveled outer end of the plunger I42. When it is desired to fire theaction, the safety plunger I42 is retracted by pushing the lever I60 forwardly to permit the,

sear-receiving hp 1 E6 of the hammer to become engaged with the sear I it of the trigger. Thereafter, the trigger I20 may be pulled upon to release the hammer 88 and permit the striking face thereof to engage the firing pin I06.

After firing, the cooking procedure is repeated, whereupon the extractor I62 functions to move the fired cartridge I "M rearwardly out of the chamber of the barrel by reason of the engagement of the spring-pressed lip i 'H) with the groove I12 of the cartridge and the rearward shifting of the extractor by engagement of the projection 68 of the cocking lever with the shoulder I18 of the extractor. With the action in its open .position as shown in Fig. 5, the fired cartridge may be removed and replaced with a live cartridge to once again condition the firearm for firing.

While a single preferred embodiment of the invention has been disclosed in detail, it will be understood that various modifications with regard .to constructional details may be resorted to without departing from the spirit of the invention or the scope of the following claims.

I claim:

1. In a firearm: a vertically slotted frame chambered at one end to receive a barrel; a pivoting block pivotally carried in said frame for swinging movement into and out of abutting engagement with the chambered barrel-receiv ing portion of said frame, said pivoting block being formed with a cocking shoulder; a firing pin carried within said pivoting block for limited longitudinal sliding movement and arranged to projecting outwardly on either side of said pivoting block; a sliding block positioned adjacent to one side of said pivoting block and slidably carried by said pivoting block for limited vertical .movement'with respect to saidpivoting block; a hammer pivotallycarried within said sliding block and having a cooking projection thereon engageable with the cocking shoulder of said pivoting block upon relative vertical sliding movement between said pivoting and sliding blocks for swinging said hammer from a firing position to a cocked position within said sliding block, said hammer, when occupying its firing position, being engageable with said firing pin to project the. latter outwardly from the side of said pivoting block adjacent the chambered portion of said frame; spring means connected between said hammer and said sliding block for urgingsaid hammer to its firing position; a trigger pivotally mounted in said sliding block and having a finger-receiving lever and a sear engageable with said hammer to releasably hold said hammer in its cocked position, said trigger being pivotally movable in said sliding block to engage or disengage the sear with ,or from said hammer; adjustable tension spring means carried between said trigger and said sliding block and urging said trigger to swing to a position to engage the sear with said hammer; and .a manually-operable cocking lever pivotally carried in said frame along the pivotal axis of said pivoting block and slidably connected with said sliding block and having a projection thereon engageable with said pivoting block, said cocking lever being movable to slide said sliding block vertically with respect to said pivoting block and to swing the latter into and out of abutting engagement with the chambered portion of said frame.

2. In a firearm firing mechanism: a frame having a barrel-receiving chamber; a compound breechblock assembly comprising a first pivoting.

block pivotally mounted in said frame for swinging movement between a position abutting one end of the barrel-receiving chamber of said frame and a second position providing unobstructed access to said chamber, and a second sliding block slidably carried by said pivoting block and pivotally movable therewith, said sliding block being positioned on the side of said pivoting block opposite the barrel-receiving chamber of said frame and being movable vertically with respect to said pivoting block; a firing pin extending through and slidable in said pivoting block; a striking hammer pivotally carried in said sliding block for swinging movement between cocked and firing positions; means stationarily carried by said pivoting block for moving said hammer between its firing and cooked positions upon relative downward sliding movement of said sliding block with respect to said pivoting block; and a cooking lever pivotally mounted in said frame and movable in one direction to first slide said sliding block downwardly with respect to said pivoting block and to there-' after swing said pivoting block to its position away from the barrel-receiving chamber of said frame.

3. In a firearm firing mechanism: a frame formed with a chamber to receive a barrel; a compound breechblock assembly pivotally mounted within said frame for swinging movement into'and out of registration with the barrelreceiving chamber of said frame, said breechblock assembly including a first pivoting block section arranged to pivotally swing between a firstposition adjacent to the chamber of said frame and a second position providing unobstructed access to the chamber of said frame, and a second sliding block section slidably carried on :the pivoting block sectionxfor relative vertical movement with respect thereto; a firing pin extending through the pivoting block section of said breechblock assembly and carried therein for limited longitudinal sliding movement; a cam abutment on the pivoting block section of said breechblock assembly; a hammer pivotally mounted within the sliding block section for swinging movement between firing and cocked positions, said hammer, when occupying its firing position, being engageable with one end of said firing pin; a cam follower on said hammer engageable with said cam abutment upon relative downward vertical movement of the sliding block section with respect to the pivoting block section for moving said hammer between its firing and cooked positions; spring means connected with said hammer and resiliently urging the latter toward its firing position; manually-operable trigger means pivotally carried within the sliding block section of said breechblock assembly and having a sear thereon engageable with said hammer for releasably holding the latter in its cocked position; and a manually-operable cocking lever pivotally mounted within said frame and slidably connected with the sliding block section of said breechblock assembly, said cocking lever having a projection thereon engageable with the pivoting block section of said breechblock assembly for swinging the latter within said frame, said cocking lever being movable in one direction to first slide the sliding block section relatively downwardly with respect to the pivoting block section and for thereafter swinging said pivoting and sliding block sections into and out of registration with the chamber of said frame.

4. In a firearm firing mechanism: a frame having a barrel-receiving chamber; a compound breechblock assembly comprising a first pivoting block pivotally mounted in said frame for swinging movement between a position abutting one 10 end of the barrel-receiving chamber of said frame and a second position providing unobstructed access to said chamber, and a second sliding block slidably carried by said pivoting block and pivotally movable therewith, said sliding block being positioned on the side of said pivoting block opposite the barrel-receiving chamber of said frame and being movable vertically with respect to said pivoting block; a firing pin extending through and slidable in said pivoting block; a striking hammer pivotally carried in said sliding block for swinging movement between cocked and firing positions; means stat-ionarily carried by said pivoting block for moving said hammer between its firing and cooked positions upon relative downward sliding movement of said sliding block with respect to said pivoting block; a cooking lever pivotally mounted in said frame and movable in one direction to first slide said sliding block downwardly with respect to said rolling block and to thereafter swing said pivoting block to its position away from the barrel-receiving chamber of said frame; and spring means connected with said cockin lever for urging the latter to move in the opposite direction.

JOHN LE B. ARBUCKLE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 269,546 Starr Dec. 26, 1882 433,260 Walsh July 29, 1890 1,448,297 Hedrick Mar. 13, 1923 1,459,108 Lewis June 19, 1923 1,494,105 Elder May 13, 1924 2,289,098 Buhmiller July 7, 1942 

